Most of them are so ineffective except at such large doses as to be poisonous for adults.
You wanted a holistic answer, how about everything you described is likely due to being in pain.
Acetaminophen relieves pain with very low risk to the liver. OD must be VERY intentional.
For drug-free pain-management, try something that distracts your toddler's mind, like ginger tea or capsaicin (hot peppers).
Your toddler will eat when they're hungry. It's quite surprising at how well humans 'know their own body.
Children aren't plants. They only grow horizontally if overfed.
On the liver risk, Tylenol is way lower risk than eating sugar, honey, nectar and HFCS (because all are half fructose and fructose is to the liver as is alcohol: poisonous when consumed in large quantity and chronically ).
Sorry if I got all 'sciency' on you.